"Programming languages are living phenomena: They're born, the lucky ones that don't die in infancy live sometimes long, fruitful lives, and then inevitably enter a period of decline. Unlike real life, the decline can last many, many years as the presence of large legacy codebases means practiced hands must tend the code for decades. The more popular the language once was, the longer this period of decline will be."

People finally discovered that single paradigm languages are not a good idea.

I disagree. Maintaining a clear, precise focus is a Very Good Thing (see: Coupling and Cohesion 101). You never see a joiner using the same tool to do everything from slice wood to turn screws to drive nails to apply varnish. There's a reason for that.

I think the real problem is developers not being able to hop quickly and effortlessly between different languages within a project. That may be partly down to bridging and tools not being good enough to allow seamless mixing and matching. But I suspect the biggest barrier is developers themselves lacking the mental agility to switch between languages and idioms. That, compounded by a self-indulgent fondness for inventing complex solutions using tools they already know rather than seeking out simple solutions involving tools they don't. The modern trend for Computer Science courses to silently retool as Software Engineering, and from there to lowest-common-denominator Java diploma mills, probably doesn't help either; but that's another debate.